Animal breeding or keeping is accompanied with an offensive smell mainly comprising ammonia, triethylamine, and sulfides. Deodorization in animal breeding or keeping has been effected with adsorbents, such as activated carbon, zeolite, bentonire, and impregnated pulp, and deodorant sprays. In keeping, e.g., cats indoors, since excrements of cats give off an awful smell, zeolite, bentonire, siliceous sand, etc. are used as toilet sand, which is disposed after each use. However, if these non-combustible materials are disposed together with combustible garbage, such would be a cause of obstruction of public facilities of garbage incineration, giving rise to a serious social problem.
Impregnated pulp, which has recently been extending its use because of its combustibility, has poor deodorizing effects. Moreover, since it is easily electrified, it adheres to the paws, making the floor dirty. The same disadvantage also applies to activated carbon.
Deodorant sprays only show a slight masking effect, furnishing no fundamental means of deodorization.
Thus, the problem of smell associated with animal breeding or keeping has not yet come to a satisfactory solution. Besides the problem of domestic animals, in cities of growing population, there is an increasing demand for a solution to the problem of smell of laboratory animals from the standpoint of environmental hygiene in the neighborhood.